This invention relates to a microscope stage in which a stage is guided for movement along a single rail structure disposed adjacent one edge of the stage parallel to the direction of the movement.
Microscope stages are well known in the prior art, for example, in U.S. Pat. No. 1,187,970, which discloses a stage with anti-friction wheels bearing on a surface of the microscope table, the stage having scales to record the position of the stage relative to the microscope table. The stage is also provided with a hold down spring to hold a slide against a flange of the microscope table. The stage of this prior art is not attached to the microscope table and requires being hand held in place for stability.
U.S. Pat. No. 4,262,991 provides a microscope stage displaceable in two coordinate directions with spring loaded guide means to maintain stage and base in captive alignment using a pair of parallel grooves and rails spaced apart by a substantial portion of the width of the stage. This arrangement, when a stage is wider than it is long results in too much friction when provided with opposing contact point preload sufficient to provide smooth, predictable and stable movement of the stage relative to the base.
The inventor of the present invention has been granted a number of United States Patents for component precision positioning stages for example, U.S. Pat. No. 6,266,184 which discloses a stage supported on opposite side edges by and for movement along a pair of rails engagement with which is by means of a spring bias. This arrangement is satisfactory when the width of the stage is narrower than its length in the direction of travel of the stage along the rails. However, when the width is greater than the length, twisting forces make it difficult or impossible, without excessive friction losses to maintain proper contact with the spaced rails. This results in jerky and/or imprecise movement of the stage.
It is an object of the present invention to provide a microscope stage which provides smooth low friction predictable and stable sliding movement relative to a base which may be affixed to or part of a microscope table, particularly when the stage is shorter along its direction of movement than its width normal to that direction.
It is a further object of the invention to provide a microscope stage guided and supported by a single support and guide structure.
The invention provides a microscope stage, supported on a base, for movement in a direction of travel relative to the base by a resiliently biased single support and guide structure, which are disposed adjacent an edge of the stage, an opposed edge of the stage being supported on the base.
According to the invention, there is provided a microscope stage, comprising: a stage supported on a base for movement relative to the base in a direction of travel, the stage having opposed parallel edges extending in the direction of travel, and extending between opposed ends of the stage; the stage and base together define a single stage support and guide structure disposed adjacent one of the edge of the stage, the structure including a rail extending along the direction of travel and engaged by a guide for guiding the stage along the rail in the direction of travel, wherein the rail and guide are biased into contact with each other by a spring device and wherein the stage is supported by the base adjacent the other of the edges of the stage.
The invention is particularly applicable to microscope stages defined in the preceding paragraph in which the length of the parallel edges is less than the length of the opposed ends (e.g. the width of the stage).